[unreadable] We used insertional mutagenesis in zebrafish to identify genes essential for early development. We isolated ~550 recessive embryonic lethal mutations and are maintaining them as heterozygous lines. These lines harbor mutations in ~25% of the genes that can be identified by a visual screen of 5-day old zebrafish larvae for any morphological defect. To date we have cloned 70% of the mutated genes. About 20% of the genes are novel and almost all have human homologues. Some of the genes are already known to be mutated in human diseases. [unreadable] [unreadable] We request funds for a supplement so that we can work with multiple labs to rapidly and fully characterize this mutant collection phenotypically. Thus the goal of the supplement is to allow the rapid exploitation of the mutant collection by the zebrafish and wider scientific communities. Specifically we wish to carry out multiple re-screens ("shelf-screens") of this collection to find specific mutants of interest to multiple labs. This urgent need arises because 1) to re-establish several hundred lines of heterozygous mutant fish that can be screened within a few weeks at the Oregon Stock Center will take two to three years, delaying the use of the collection by the community for at least that long; 2) additional work is still needed to confirm mutant gene identities and this can best be done with assistance from our lab while the screens are being done; and 3) we have received over 20 requests from leading scientists in the field to shelf screen the collection immediately for a diversity of phenotypes. [unreadable] [unreadable] The goals of the parent grant were to complete the isolation of the mutants and to clone the mutated genes, to shelf-screen the collection for several phenotypes of interest to members of our own lab, and to transfer all the mutant lines to the Oregon Stock Center. The specific goals of the supplement are, in addition, to: 1) Carry out shelf screens for other labs including screening for defects in the development of heart, fins, eye, skin, pituitary, hypothalamus, brain ventricles, muscle, blood stem cells, vasculature, thyroid, and thymus, as well as defects in axon guidance, lipid metabolism, oxidative stress, wound healing, growth control and cancer; 2) Advertise this resource to the community via ZFIN and carry out additional screens as requested on a first come first serve basis or according to an alternative plan for rapid and fair use; 3) Work with ZFIN to incorporate the data obtained from this project into a common data [unreadable] base. [unreadable] [unreadable]